If Firefox has been feeling sluggish for you lately, you might be able to cut down on some of those UI hangs with an about:config tweak.

The Mozilla team is working on a number of performance tweaks for upcoming versions of Firefox, one of which is the use of a new HTTP cache that should fix some UI hang issues. It isn't enabled by default yet, but will be soon—and you can enable it right now with an about:config tweak. To do so:

Enter about:config into Firefox's address bar and press Enter.

Search for the browser.cache.use_new_backend flag and double-click on it.

Change its value from 0 to 1 to enable the new cache. (You can flip it back at any time by changing it back to 0).

Close about:config and continue browsing—no need to restart or anything.

I enabled it and while it hasn't been a silver bullet, it seems to have helped decrease the number of times the browser screeches to a halt. Check out the link below for more info, and while you're digging around in about:config, check out some of our other favorite tweaks.